如何普判断CPU大端小端

/*
 *文件：chackCPU.c
 *时间：2010.9.25
 *作者：qiang
 *说明：检测CPU是little-endian or big-endian
 */

#include <stdio.h>
static union{
    char c[4];
    unsigned long mylong;
    }endian_test={{'l','?','?','b'}};
#define ENDIANNESS ((char)endian_test.mylong)

int main(int argc,char* argv[])
{
    if(ENDIANNESS=='l')
        printf("qiang,CPU type is little-endian! \r\n");
    if(ENDIANNESS=='b')
        printf("qiang,CPU type is big-endian! \r\n");
    return 0;
}